Apparatus and process for the production of a superconductive layer

Abstract

An apparatus and process for applying a superconductive layer on an elongate substrate that includes moving the elongate substrate through a heating zone, applying a pulsed laser beam against a target, having a length, that is coated with superconductive material wherein particles of superconductive material are separated from the target and strike the elongate substrate with a plasma beam in the heating zone, and oscillating the pulsed laser beam across the target to provide a substantially uniform coating of superconductive material on the elongate substrate.

We claim:  
     
       1. A process for applying a superconductive layer on an elongate substrate comprising: 
       moving said elongate substrate through a heating zone;  
       applying a pulsed laser beam against a target of superconductive material over a length of the target whereby a superconductive material is separated from said target and strike said elongate substrate heated in said heating zone;  
       linearly oscillating said pulsed laser beam across said target to linearly scan the surface of the target in a scan direction; and  
       rotating said target 180° within its surface plane after at least one laser scan has been completed.  
     
     
       2. The process for applying a superconductive layer on an elongate substrate according to  claim 1 , wherein said oscillating of said pulsed laser beam across said target includes directing said pulsed laser beam to a laser beam deflector that can reflect said pulsed laser beam across said length of said target. 
     
     
       3. The process for applying a superconductive layer on an elongate substrate according to  claim 2 , wherein said laser beam deflector includes a pivotable mirror. 
     
     
       4. The process for applying a superconductive layer on an elongate substrate according to  claim 3 , wherein said pivotable mirror is oscillated back and forth so that said pulsed laser beam covers said length of said target to uniformly apply said superconductive layer on said elongate substrate with said plasma beam. 
     
     
       5. The process for applying a superconductive layer on an elongate substrate according to  claim 1 , further includes rotating said target at least one hundred and eighty degrees. 
     
     
       6. The process for applying a superconductive layer on an elongate substrate according to  claim 5 , further includes interrupting said laser beam prior to said rotation of said target at least one hundred and eighty degrees. 
     
     
       7. The process for applying a superconductive layer on an elongate substrate according to  claim 1 , wherein oscillating said pulsed laser beam across said target to provide a substantially uniform coating of superconductive material on said elongate substrate is at a frequency (F 1 ) represented by the equation: 
       
         
           F 1 =K×F/(L/A)  
         
       
       where K is a coefficient between the values of 0.5 and 8.0, F is a repetition rate of said pulsed laser beam in cycles per second, L is said length of said target in millimeters over which said pulsed laser beam oscillates and A is a constant that corresponds to 1 millimeter. 
     
     
       8. The process for applying a superconductive layer on an elongate substrate according to  claim 5 , wherein said target is rotated one hundred and eighty degrees after said pulsed laser beam strikes said length of said target in a range of between one and ten times. 
     
     
       9. The process for applying a superconductive layer on an elongate substrate according to  claim 1 , wherein said oscillating of said pulsed laser beam across said target corresponds to a saw tooth waveform. 
     
     
       10. The process for applying a superconductive layer on an elongate substrate according to  claim 1 , wherein said elongate substrate is helically wound around a pipe. 
     
     
       11. The process for applying a superconductive layer on an elongate substrate according to  claim 1 , further includes rotating said elongate substrate as said elongate substrate moves through said heating zone. 
     
     
       12. The process for applying a superconductive layer on an elongate substrate according to  claim 1 , wherein said elongate substrate is moved through a heating zone in a linear manner. 
     
     
       13. The process for applying a superconductive layer on an elongate substrate according to  claim 1 , further includes injecting oxygen into said heating zone. 
     
     
       14. The process for applying a superconductive layer on an elongate substrate according to  claim 13 , wherein said injecting of oxygen into said eating zone is pulsed. 
     
     
       15. The process for applying a superconductive layer on an elongate substrate according to  claim 1 , further includes injecting oxygen into said heating one between pulses of said laser beam. 
     
     
       16. The process for applying a superconductive layer on an elongate substrate according to  claim 1 , wherein said heating zone is in a deposition chamber, and further including injecting oxygen into said heating zone through a second opening in said deposition chamber that is diametrically opposite a first opening in said deposition chamber that receives said plasma beam from said target. 
     
     
       17. An apparatus for applying a superconductive layer on an elongate substrate comprising: 
       a deposition chamber having a heating zone through which the elongate substrate can be moved;  
       a laser that can apply a pulsed laser beam;  
       a target formed from a superconductive material and having a length;  
       an oscillating mechanism to move said pulsed laser beam across said target in a scan direction whereby said superconductive material is separated from said target and strike said elongate substrate heated in said heating zone;  
       a rotation mechanism for rotating said target by 180° within its surface plane; and  
       a control unit for controlling the sequential movement of the laser beam and rotation of the target.  
     
     
       18. The apparatus for applying a superconductive layer on an elongate substrate according to  claim 17 , wherein said oscillating mechanism includes a laser beam deflector that can reflect said pulsed laser beam across said length of said target. 
     
     
       19. The apparatus for applying a superconductive layer on an elongate substrate according to  claim 18 , wherein said laser beam deflector includes a pivotable mirror. 
     
     
       20. The apparatus for applying a superconductive layer on an elongate substrate according to  claim 19 , wherein said oscillating mechanism further includes mechanism to oscillate said pivotable mirror back and forth so that said pulsed laser beam covers said length of said target. 
     
     
       21. The apparatus for applying a superconductive layer on an elongate substrate according to  claim 17 , wherein said oscillating mechanism moves said pulsed laser beam across said target in correspondence with a saw tooth waveform. 
     
     
       22. The apparatus for applying a superconductive layer on an elongate substrate according to  claim 17 , further includes a mechanism that rotates said elongate substrate as said elongate substrate moves through said deposition chamber. 
     
     
       23. The apparatus for applying a superconductive layer on an elongate substrate according to  claim 17 , further includes a mechanism that moves said elongate substrate linearly through said deposition chamber. 
     
     
       24. The apparatus for applying a superconductive layer on an elongate substrate according to  claim 1 , further a mechanism that injects oxygen into said deposition chamber. 
     
     
       25. The apparatus for applying a superconductive layer on an elongate substrate according to  claim 24 , wherein said mechanism that injects oxygen into said deposition chamber injects said oxygen in pulses. 
     
     
       26. The apparatus for applying a superconductive layer on an elongate substrate according to  claim 24 , wherein said mechanism that injects oxygen into said deposition chamber injects said oxygen between pulses of said laser beam. 
     
     
       27. The apparatus for applying a superconductive layer on an elongate substrate according to  claim 24 , wherein said mechanism that injects oxygen into said deposition chamber, injects said oxygen through a second opening in said deposition chamber that is diametrically opposite a first opening in said deposition chamber that receives said plasma beam from said target. 
     
     
       28. The process according to  claim 1  wherein the target is moved perpendicularly to said scan direction. 
     
     
       29. The process according to the  claim 28  wherein said moving of the target perpendicularly to said scan direction is performed after at least one linear scan has been completed. 
     
     
       30. The process according to  claim 1  wherein the target and the substrate are arranged in parallel. 
     
     
       31. The apparatus according to  claim 17  wherein the target is shiftable periodically in a direction perpendicular to said scan direction. 
     
     
       32. The apparatus according to  claim 17  wherein the target and the substrate are arranged in parallel.